Adi Shankara, the renowned Indian philosopher and theologian who propagated Advaita Vedanta, did not explicitly reject the caste system in his writings. However, his teachings emphasized the concept of the ultimate reality (Brahman) being beyond caste, creed, or social status.
Shankara emphasized the idea of spiritual liberation (moksha) as the ultimate goal of human life, and he taught that this liberation was accessible to all individuals regardless of their caste or social background. His philosophy emphasized the unity of all existence and the idea that the true nature of the self (Atman) is identical to the ultimate reality (Brahman), transcending any distinctions based on caste or social status.
While Shankara himself did not openly challenge the caste system, his teachings of Advaita Vedanta have been interpreted by some scholars and followers as implicitly critiquing the caste system by emphasizing the fundamental equality of all beings in the eyes of Brahman. Additionally, Shankara's emphasis on spiritual realization as the highest goal may have indirectly undermined the hierarchical social structures inherent in the caste system. However, it's essential to note that interpretations of Shankara's views on the caste system may vary among scholars and followers of Advaita Vedanta.